PMID: 9753329 , Related PDB id: 1BOL
Rao VD, Misra S, Boronenkov IV, Anderson RA, Hurley JH
Structure of type IIbeta phosphatidylinositol phosphate kinase: a protein kinase fold flattened for interfacial phosphorylation.
Cell. 1998 Sep 18;94(6):829-39.
Phosphoinositide kinases play central roles in signal transduction by phosphorylating the inositol ring at specific positions. The structure of one such enzyme, type IIbeta phosphatidylinositol phosphate kinase, reveals a protein kinase ATP-binding core and demonstrates that all phosphoinositide kinases belong to one superfamily. The enzyme is a disc-shaped homodimer with a 33 x 48 A basic flat face that suggests an electrostatic mechanism for plasma membrane targeting. Conserved basic residues form a putative phosphatidylinositol phosphate specificity site. The substrate-binding site is open on one side, consistent with dual specificity for phosphatidylinositol 3- and 5-phosphates. A modeled complex with membrane-bound substrate and ATP shows how a phosphoinositide kinase can phosphorylate its substrate in situ at the membrane interface.